Automatic choke device for shotguns



July 14, 1959 R. G. HARE AUTOMATIC CHOKE DEVICE FOR SHOTGUNS Filed Nov. 9, 1955 /QoberL G, Hare,

INVENTOR.

AUTOMATIC CHOKE DEVICE FOR SHOTGUNS Robert G. Hare, Sharon, Mass., assignor to Hartford Gun Choke Company, Inc., Newington, Conn., a corporation of Connecticut Application November 9, 1955, Serial No. 545,931

7 Claims. (Cl. 42,-79)

This invention relates to choke devices attachable to `the muzzles of shotguns and operable automatically on the tiring of the rst shot, to effect an increased choke eect for any subsequent shot.

For some time, choke devices have been available that were manually adjustable to provide whatever choke eiect best suited the existing requirements. t For duck shooting, for example, a fuller choke would normally be selected than would be wanted in hunting upland game. While such choke devices render pump and semi-automatic Shotguns adaptable to a wider range of shooting than a double barreled arm, the latter, having one barrel more fully choked 4than the other, enables an effective second shot to be made at a distance greater than that for which the first-fired barrel was intended.

There is, accordingly, a need for such a choke device that is automatic in operation so that, on each setting, a fuller choke will be provided on the ring of the first shot thus to adjust the shotgun to increasing ranges. The provision of such an automatic choke device is the principal objective of the invention with other objectives being bases of adjustment that enable a desired choke range to be established with light as well as magnum loads. v

These objectives are attained, in accordance with the invention, by providing a shotgun choke comprising a member threaded for attachment to the muzzle of a shotgun barrel and having resilient choke fingers. The member is within a slidable unit whose forward movement, in response to the firing of a shell, is yieldably and preferably adjustably opposed. In addition, the unit is provided with surfaces engageable with corresponding linger surfaces and operable to eifect their radial inward movement on forward movement of the unit and preferably, the relationship between these surfaces is also adjustable.

In the accompanying drawings, there is shown an illustrative embodiment of the invention, from which these and other of its objectives, novel features, and advantages will be readily apparent.

In the drawings:

Fig. 1 is a longitudinal section of a choke device in accordance with the invention attached to a shotgun barrel,

Fig. 2 is a similar view taken at right angles to Fig. 1 and with the resilient choke fingers shown in elevation,

Fig. 3 is a fragmentary view, similar to Fig. 1, illustrating another embodiment of the invention, and

Fig. 4 is a similar View of a further modification of the invention.

In accordance with the invention, the muzzle of a shotgun barrel 5 is threaded as at 6 to receive a member 7 provided with resilient choke lingers 8 and having a groove 9 to receive the extremity 10 of the sight 11 threaded through the sleeve 12 of the generally indilnted States Patent; 0

cated unit 13` which is axially slidable relative vto the member 7.

` At its rear end, the sleeve 12 is threaded as at 14 to receive the threaded end of a tubular stop 15 by Which a spring 16 is held compressed against the prox-imate end of the member 7 and by which the resistance of the spring 16 may be adjusted to meet the shooters requirements. It may be so Atensioned as to give the desired automatic step-up of the choke eifect or so tensioned as to prevent the automatic change of a selected setting.

'Ihe front end of the sleeve 12 is threaded as at 17 to receive the second sleeve 18 which is shown as including a recoil ltube 19. The sleeve 18 has cam surfaces 20 engageable with like surfaces 21 of a split ring 22 loosely confined between the extremity of the sleeve 12 and the shoulder 23 of the second sleeve 18 to enable the extent to which it is contracted to be adjusted by turning the sleeve 18 relative to the sleeve 12.

The inner surface of the ring 22 is shown as forwardly and outwardly flared as at 24 for wedging engagement with similarly disposed portions 25 on the outer surfaces of the resilient lingers 8 so that as the unit 13 is moved forwardly in response to the thrust of gas each time a shell is iired, the fingers 8 are wedged radially inwardly from their normal position, preferably defining a slightly modified cylinder.

- When wanted, a friction brake may be provided. An eifective brake such as that shown in Fig. 3 may comprise -a split ring 26 located between the stop 15 and the spring 16.

' The ring Z6 and the proximate end of the stop 15 are formed with complemental wedge surfaces to eifect as the lstop 15 is thrust forwardly the Wedging of the ring 26 radially inwardly into braking engagement with the barrel 5. i

If preferred, the brake arrangement disclosed in Fig. 4 may be employed. In that embodiment of the in vention, a `split ring 27 is disposed between the spring 16 and the rear end of the member 7 and the proximate face of the ring 27 and the member 7 are formed with complemental surfaces -to eiect on forward movement of ythe stop 15 radial outward movement of the ring 27 into braking engagement with the sleeve 12.

In operation, it will 'be appreciated that it is necessary to adjust each -installed choke device. Such adjustments are in relation to the pattern effect wanted and to the loads used. For example, a user may wish to have, for upland game shooting, his rst shot an improved cylinder and other shots subject to a modified choke with standard loads. For duck shooting, he might wish to use magnum loads and to have second and any subsequent shots subject to a full choke.

Adjustment for choke effects may be effected by turning the second sleeve 18 relative to the first sleeve 12 While adjustment in relation to the loads used is accomplished by suitably varying the compression of the spring 16.

After the desired adjustments of the installed device have been made, the first shot automatically results in the desired choke effect for other shots since the attendant forces cause the unit 13 to move forward against the action of the spring 16 to cause predetermined constriction of the choke fingers 8.

From the foregoing, it will be apparent that a choke device in accordance with the invention is well adapted to meet the requirements of both use and manufacture.

What I therefore claim and desire to secure by Letters Patent is:

1. A choke for a shotgun barrel comprising a member threaded for attachment to said barrel, and including resile'rit choke fingers, a unit slidably connected to said member and comprising a first sleeve, a st-op threaded to the rear end .of said sleeve lin spaced relationship to the rear end of said member, a compression spring between said stopA and said rearend and urging said unit rearwardly, a second sleeve threaded on the `other endk of said first sleeve, a finger-engaging ring backed by said first sleeve, said ring and said second sleeve including coacting wedge surfaces ywhereby-axial adjustments of said second sleeve relative lto said first sleeve effect radial adjustments of said fingers, said fingers and said ring also including coacting wedge surfaces whereby forward axial movement of said unit relative to said member is effective to constrict `said fingers, and brake means housed by said first sleeve and including first and second parts provided with coacting cam surfaces, saidrst part being longitudinallymovable and said second part being actuated radially in response to such longitudinal movement.

2. A choke for a shotgun barrel comprising a member threaded for` attachment to said barrel and including resilient choke fingers, a finger constricting unit slidably connected -to said member and comprising a sleeve, adjustable means for yieldably opposing forward motion of `said unit interposed between said first `sleeve and the rear end of said member, and brake means housed by said sleeve and 4including first and second parts provided with coacting cam surfaces operative on longitudinal movement of lthe first. part vto effect radial braking engagement of said second part.

3. In a choke for a shotgun barrel, a member threaded for attachment to said barrel and including resilient choke fingers provided with first wedge surfaces, a unit slidably connected to said member and comprising a rst sleeve, a stop 4threaded to the rear end of said' sleeve in spaced-relationship to the rear end of said member, av compression spring between said `stop and said rear end and urging said unit rearwardly, a second sleeve threaded on the other end kof said first sleeve including second wedge surfaces, said surfaces being coactive on movement of said unit in relation to said first sleeve to effect radial movement of said ngers, and brake means housed by said first sleeve and including first and second `parts` provided with coacting cam surfaces opera- -tive on longitudinal movement of the first part to effect radial braking engagement of the second part.

4. The choke of claim 3 in which the radial braking engagement of the second part is with the barrel.

5. The choke of claim 3 in which the radial braking engagement ofthe ysecond part is with the member. V

6. A choke for a shotgun barrel comprising a member threaded `for attachment ltoV said' barrel `and including resilient choke fingers, a unit slidably connected torsaid member and operable on forward movement thereof to constrict saidfingers, saidunit including a sleeve, a stop threaded to lthe rear end of said lsleeve in spaced relationship -to the rear endv of said member, a compression spring between said stop and said rear end and urging said unit rearwardly, and brake means including a resilientmsplit/,ring associated with `said spring and operated therebytonbrake forward movement of said unit.m '1. A choke for a shotgun barrel comprising a member lthreaded for attachment to said barreland including resilient choke' fingers, a unit slidablyconnected to said memberV and Voperable on forward movement thereof toconstrict said fingersy and including a sleeve, akstop threaded to the rearendof saidrmember, and resilient, radially movable' brakel means housed by saidV sleeve `and including hrst and second parts provided with coactifng cam surfaces, said first part being longitudinally movable and said second part being actuated radially in dresponse to such longitudinal movement for braking engagement with said sleeve.

References Cited in the file of this patent UNITED STATES PATENTS 2,134,238 Sedberry Oct. 25, 1938 2,417,721 Whedon Mal. 18, 1947 2,558,200 Schmeling June 26, 1951 2,676,429 Gotterson Apr. 27, 1954 2,685,144 Schroeder Aug. 3, 1954 2,759,286 Moore Aug.-21, v1956 2,765,564- Schroeder Oct. 9, 1956 

